Script to remove lines using sed.

removeLine.sh

#!/usr/bin/env bash
#
# Very simple shell script that removes a line from a file
# using sed.
#
# Usage: removeline 13 /path/to/file
#

nParams=$#

# Verify that there are more than two parameters
if (( nParams < 2 )); then
    echo "Removes a single line from a file."
    echo -e "\n\tUsage: removeline number file"
    exit 0
fi

# Verify that the first parameter is a valid integer.
if [[ $1 =~ ^[[:digit:]]+\,{0,}[[:digit:]]{0,}$ ]]; then    
    
    # Check the file for existence and actually do it
    if [ -e $2 ]; then
        sed -i '' $1d $2
    else
        echo "File provided does not exist."
        exit 1
    fi
    
else
    echo "First argument must contain a line number or range."
    exit 1
fi

# Default to a successful exit
exit 0